Coin testing device



Feb. 21, 1939. E. QEASON 'COIN TESTING DEVICE 2 Sheets-Sheet l Filed July 3l, 1936 A INVENTOR. ERA/6? o. 46o/V ATTORNEY.

Patented Feb. 21, 1939 UNITED STATES PATENT OFFICE 15 Claims.

This invention relates to improvements in coin controlled devices and has reference more particularly to an improved coin testing mechanism for use with a coin controlled vending device.

In the dispensing of many kinds of merchandise, vending devices have been invented and used, which do not require an attendant, but which are controlled by a coin and operate to deliver a quantity of merchandise Whose` value Y 10 at the then market price equals the value of the coin.

It is found, by` experience, that some people cannot resist the temptation to employ slugs of the shape and size of the coin or coins with which 15 the device has been designed to operate, and oftentimes. these slugs are so expertly made that they will pass the ordinary tests to which such vending devices usually subject them. Such slugs are, of course, usually made of a base metal,

20 such as copper, but, onaccount of the segniorage,

silver slugs can also be substituted for the silver coins with profit.

It is obvious-that automatic coin controlled dispensers-cannot be successfully operated unless some means is provided that will accept only regularly` minted coins, and reject all slugs, re-

gardless of the material of which they are made.

It is evident, however, that silver slugs of the sameshape, size, weight and density-as regularly 30 minted coins cannot `be distinguished by any apparatus of practical construction. The slugs employed for the purpose of operating vending machines are, however, usually rather indiiferently made, with theresultthat some of their physical properties, vsuch as their electrical conductivity, their. elasticity or their magnetic properties differ from those of regularly mintedcoins.

The materials usually employed for slugs are iron, copper, brass, zinc, tin, lead and aluminum. 4 Iron, being magnetic, can be rejectedcby some magnetic means, and offers no difficult problem. Lead, tin, and zinc, differ quite widely from silver in their elastic properties, and can be separated by a bouncing test. Copper metals which have ,L5 been subjected, during manufacture, to high pressure, are` the most difficult to detect, because such slugs have an elasticmodulus so nearly the same as silver that they will frequently pass the elasticity test, for it is `evident that such machines, 0 as` are here under consideration, cannot be too closely adjusted.` The Smithsonian tables give the hardness of pure silver and purecopper as 2.5-3crequal one to the other. Silver coins contain tenv per cent of copper` andthis` alloy is 55harder. than pure` copper, which increases the rebound velocity. The electrical conductivity remains substantially the same as that of pure silver.

It has been found that silver, copper, bronze and brass are affected somewhat differently by an alternating magnetic field. An alternating or variable magnetic flux produces a repulsive effect on all non-magnetic metals, and this varies very appreciably between different metals and alloys, and is substantially the same for copper or copper alloys and for pure silver, or silver of such purity as is used in United States silver coins, and this property is taken advantage of in the present device to effect the desired selection.

The method of effecting a selection between silver coins and slugs, which is employed in this invention consists in dropping the coins and slugs from a given height, onto an inclined surfaceof elastic material, such as steel, which surface is preferably inclined with respect to the path followed by the coin in dropping. The coin, or slug, striking the elastic surface, or anvil, rebounds along a different path and at a velocity proportional to its elasticity. Silver coins, being of a uniform density and elasticity, will follow a given path, while slugs of similar shape and size, but of less elasticity, will rebound at less velocity, and in this way, separation can be effected. Since coinage silver is harder than copper, its rebound velocity will be greater and since the momentum varies with the square of the velocity, silver coins will pass through a field that will inhibit the copper coins or slugs from passing.

After the coins have rebounded from the anvil, they are made to pass through an alternating magnetic field, whose density is so regulated that it will permit a silver coin to pass and reach a position on an inclined support located beyond this field, but which will so retard copper coins that they will not reach the support, and therefore fall into a reject chute. Slugs of magnetic material, such as iron, will be attracted and entirely stopped by the action of the magnet.

Copper has a slightly greater degree of conn ductivity than pure silver or coinage silver. Bronze, brass, nickel and their various alloyshave an elasticity closely comparable to coinage silver and considerably greater than pure silver, but their electrical conductivity is decidedly lower. When the coin to be tested is so located 50 as to act as a secondary for a primary coil, excited by an alternating electrical current, an induced current will be set up in the secondary or coin, the intensity of which will be directly proportional to the conductivity of the metal of 55 which the coin or slug is made, and in opposite or 180 phase with the primary which causes an alternating magnetic flux that is always in opposing relation to the primary flux.

The magnetic flux in the primary coil being in opposite phase to the magnetic flux in the secondary, (coin or slug) in effect repels the coin or slug proportionately to the intensity of the current generated in the coin, the strength or intensity of the current being proportionate to the conductivity of the metal of which the coin is made.

Brass, bronze, nickel and certain similar alloys having elasticity equal to or greater than silver, are rebounded through the path of magnetic fiux at an equal or greater velocity than silver. The intensity of the current generated in these metals being less than in silver, there will be less counl ter M. M. F. tending to prevent the slug from entering the field of magnetic flux in primary coil. This allows these metals to pass through and beyond the flux field of the coil. The coin or slug is supported on a plane inclined toward the source of impact, at an angle predetermined to allow gravity to overcome counter M. M. F. set up in these metals, and will roll down the inclined plane into the reject chute.

Copper, hardened by compression as in metals, has an elasticity slightly less but very closely approaching that of coinage silver. Therefore, the velocity from impact is nearly equal to silver. Since copper has a slightly greater conductivity than silver, it will generate a greater eddy current, and therefore a greater M. M. F., tending to prevent the secondary or coin from entering the field of magnetic flux of the primary coil. By combining the ,effects of the reduced velocity of the coin from impact on the anvil with the greater M. M. F. generated in the coin, it is prevented from passing the center of the field of magnetic flux in the primary coil and is repelled into the reject chute by its own M. M. F. combined with gravity.

By adjusting the strength of the alternating current in the primary coil all other electrical characteristics in the apparatus will be correspondingly adjusted within certain limits. The counter M. M. F. tending to prevent the silver coin from entering the field of magnetic iiux can be so adjusted as to barely permit the coin to pass into and through the magnetic field. By permitting the coin to be rebounded from the inclined anvil and through the magnetic field and allowed to come to rest on a plane support located just beyond the field of magnetic flux and inclined toward the flux field, the coin will roll by gravity toward the magnetic eld.

The angle of the inclined support is adjusted so that the counter M. M. F. repelling the coin is just great enough to prevent the force of gravity from causing the coin to roll back through the magnetic field into the reject chute located between the impact anvil and the primary coil. This arrangement of apparatus makes the return of good coins to the purchaser of the vended commodity certain, in the event of the failure of the supply of current, and by mechanical arrangement of the electrical switches may be arranged to return the coin in event of depletion of vended stock. This return action becomes automatic, since the coin will roll down the inclined support through the air gap arranged to concentrate the flux, in event there is no current flowing in the primary coil.

Aluminum has a degree of conductivity appreaching closely to that of copper and silver, and, since its specific gravity is low and its elasticity, when compared to its weight, is greater than silver it becomes necessary in this device to provide a mechanical retard to the free gravitational action to reduce the velocity of aluminum slugs when rebounded from the elastic anvil.

Having thus briefly described the invention, the mechanism by which the method is carried out will now be described, and for this purpose, reference will be had to the accompanying drawings, in which the essential elements thereof have been illustrated in their proper relation, and in which Figure 1 is a side elevation, looking at the machine from the rear side thereof, parts being broken away to better disclose the construction;

Figure 2 is a section taken on line 2 2, Figure 1;

Figure 3 is a section taken on line 3 3, Figure l;

Figure 4 is a section taken on line 4 4, Figure l;

Figure 5 is a section taken on line 5 5, Figure l;

Figure 6 is a section taken on line 6 6, Figure l;

Figure 7 is a fragmentary section, similar to that shown in Figure 6, and shows the parts in a different position;

Figure 8 is a diagram, to scale, showing the relative location of the several parts and the path followed by a silver coin and by a slug; and

Figure 9 is a fragmentary section showing a slightly modified construction.

In the following description the slugs will also be referred to as coins, because the technical distinction is not material; the method of selection depending on the physical properties, and not on the impression placed thereon at the mint.

In the drawings, numeral 5 designates a metal plate which forms a base or support for the several parts of the mechanism. The base is provided with an opening 6 whose diameter is such that it will admit a silver dollar. Secured to the base, below opening G, and to the left thereof, is a guide plate having its edge 8 vertical and the edge 9 inclined.

A pendulum-like member I is mounted to swing about a pivot Il, and has a downwardly extending narrow arm and a counterweight or head I 2, that normally rests on the stop I3. The pivot I I is so positioned that the distance between the inclined surface 9 and the opposed inclined surface I4 of the pendulum, at the height of the pivot, is slightly greater than the diameter of Ya silver dollar.

The opening 6 is positioned with its center on the perpendicular bisector of a horizontal line joining the inclined guide surfaces, and passing through the pivot. Located below the guide 'l and to the right of the inclined edge 9 extended, is an anvil I whose upper end is inclined downwardly toward the left, so as to form an angle of less than 90 with line aff-b. The dotted line, designated by reference characters c, d, e, f and g, indicates the path of the center point of a silver dollar in its passage through the device.

When a silver dollar is inserted through the opening 6, it drops, perpendicularly, until its center reaches point d when the left side thereof comes into contact with the inclined guide edge 9 after which it will slide along this edge with its center following line d c. The pendulum I0 engages the right hand side of the dollar and prevents itzfrombouncing away from the edge 9 with the` result that after` it leaves the guide edge it will travel in a substantially .straight line until itstrikes the anvil surface I6.

Upon striking the anvil surfacethe coin will rebound and `its center will follow line e--f until it strikes the stop |1, whose edge is beveled as indicated at I8 in Figure 2. A movable support I9 holdsthe coin from falling downwardly along line g` at this point.

Atriangular member Y separates the reject passage R from the passage A that leads to a coin box. As cle-arly shown in the drawings, the upper surface of the support I9 is inclined towardthe reject opening R., and it is evident that the coin` would roll downwardly and into the reject openingunless restrained by some means.

An alternating current electromagnet comprising two laminated pole pieces 2| and 22 and a coil `23 is attached to a plate 24 of brass or other non-magnetic material. The poles 2| and 22 are positionedas shown in Figure 8, from which it will be seen that the upper left hand corner of pole 2| extends up over the top of the support I9, and serves as a stop. There is no physical contact between the coin and the pole piece 2l, but the magnetic flux that crosses to the plate 5, which isof magnetic material, sets up eddy currents in the coin, and the reaction tends to urge it` toward the left, and prevents the coin from rolling. along the inclined surface. It will hereafter appear that the magnet is energized when the coin is inserted through opening 6, and remains energized until the coin is deposited in the coin box, and therefore the coin must traverse the alternating magnetic flux in its rebound along path e-f.

Whenthe coin cuts the magnetic iiuX, currents are set up which interact with the iiux to produce a, repulsive effect, whose intensity varies with the flux density and the latter must therefore be soproportioned that it will permita silver coin, like those employed for money, to pass.

A copper coin, unless highly compressed, will not be able to pass through the magnetic field, and will fall into the reject opening R. Aluminum is so light that it will be greatly retarded by the action of the pendulum l0, and will not follow line zZ-9, but will drop almost vertically after it leaves the guide edge 9 and roll into the reject opening. Coins of lead or other non-elastic metal will not bounce to any appreciable eX- tent, andwill fall into the reject opening. Coins,

- or slugs, of iron have sufcient elasticity to carry them alongpath ef, to the stop I1, but are so strongly attracted by the magnet that they are stopped thereby, and are retained by pole 22 of the magnet until the latter is de-energized, when they fall into` the reject opening. The several steps in the method can be clearly seen from Figure `8.

In order to apply the method above described, to a practical purpose, a certain mechanism must be employed and this will now be described. The stop I1 is formed by the lower end of a steel bar, designated by the same reference numeral, and which is spaced from the vertical edge 8 of the guide 1 so as to form a space for the plunger 25.

A cover plate 26` rests on the bars 1 and I1, and on the anvil I5 and separator 26, and is also provided with spacers21 and 28. The distance between the adjacent surfaces of the base 5 and the plates 24 and 26 is slightly greater than the thickness of a silver dollar.

The plunger bar 25 terminates at its lower end in aninclined surface 29 and` has a4 lateral extension 30 that covers the opening 6 whenthe bar is in its lowermostposition, as shownin Figure 1, but which will be located wholly above this opening when the plunger bar is raised before the coin is inserted. A spring 3|` tends to move bar 30 downwardly, while a dash pot 32 serves to retard its downward movement while permitting free upward movement.

Plate 5 has a slot 33 and the plunger bar has a handle 34 that projects through this slot so that the bar can be raised from the outside.

Attached at its upper end to the bar 25 is a narrow bar 35 that is provided on its right-hand edge with a cam notch 36. Bar 35 is on the outside of plate 26, and the latter carries a lever arm 31 which is mounted to turn about a pivot 3B. Lever 31 has a short arm 39 and a long arm 4|). A tension spring 4| has one end attached to the long arm, and the other anchored to the plate 26, and serves to urge the end of the arm 39 against the edge of the bar 35, and when the latter is moved upwardly from the position shown in Figure 1, it will rotate the lever 31 clock-wise about its pivot.

A shaft i2 extends between the supports 43 and fill, and carries a mercury switch that is supported by a suitable holder 46. A lever arm 41 extends from the shaft toward the plate 26, and controls the position of the switch. A rod 43 has its upper end co-nnectedwith the lever i6 and its lower end connected with arm 41, and when lever 31 is turned clockwise about its pivot, the mercury switch will be turned counter-clockwise (Figure 3) until the mercury connects the two terminals therein.

It'will be seen from this that as soon as the plunger bar is raised, for the purpose of uncovering the opening 6, the circuit from the alternating current source 49 is closed to the magnet and remains closed until the plunger returns to the position sho-wn in Figure 1.

The support I9 is formed integral with arm 50, the connection being indicated by reference numeral 5|. A link 52 is pivoted to shaft 42, and has its free end pivotally connected with the arm 59 at 59. A tension spring 54 has one end connected with the link 52 near the shaft 42, and the other end connected to arm at 55. It will be observed that spring 54 produces a force having two components, one tending t0 rncve the arm 55 upwardly, and the other tendto rotate it counter-clockwise about pivot 53. A platey 53 is attached to the arm 59, and extends outwardly therefrom.

The magnetic circuit of the magnet is formed in part by an armature 51 that is hinged to move about the pivot 58 at the outer end of the pole piece 22. The pole pieces 2| and 22 and the armature 51 are laminated and held between side pieces of non-magnetic material, one of which has been indicated by numeral 59, and this projects across the arm 56, in the manner shown mest clearly in Figure 1.

Plate 25 carries a curved arm 6|] whose end rests upon the plate 24, and serves as a stop for the support I9 when it is in the position shown in Figures i, 4 and 6.

Let us now assume that the parts are in the position shown in Figures 1, 3, 4 and 6, and that the handle 34 is grasped and moved upwardly. By the initial movement of the plunger bar 25, the lever 31 will be rocked, and the circuit to the magnet will be closed bythe mercury switch.

As: soon as the'magnet is energized, the hinged.

i' to pass through it and onto the support I9.

armature 51 is pulled towards the pole piece 2l and part 59 engages plate 56 and moves the arm 50 and support I9 towards base 5 until the support is free to move upwardly into the space between base and plate 24, when the spring 54 will act to move it into the position shown in Figure 7.

When the opening 6 has been uncovered, a silver dollar is inserted and permitted to drop, and soon thereafter it is in position on the support I9 as shown in Figure 8.

As soon as `the handle 34 is released, spring 3l starts returning the plunger bar, but this is retarded by the dash pot. The retardation does not have to be great as the time it takes theplunger bar to return does not affect the operation,

When the lower end 29 of the plunger 25 engages the coin, the support I9 will Ibegin to move downwardly, and soon thereafter switch 45 will be opened and the magnet de-energized. As the support reaches the lower edge of plate 24, it will be pulled outwardly and against the stop 60, by the spring 54, and the coin will drop into the coin box, and soon thereafter the parts will all be in the position shown in Figure 1.

If the coin is of such material that it will not reach a position on the support, the parts will return to the position shown in Figure 1, with the exception of the support I9 which will remain in the position shown in Figure 7. If a magnetic slug is used, it will be retained by the magnet pole 22 until the latter is de-energized, when it will drop into the reject opening,

Attention is called to the fact that the apparatus that has been illustrated and described has been greatly altered from the form in which it is embodied for practical operation so that the important features thereof could be more easily illustrated and explained, and it is not intended that the device, in the exact form illustrated is suitable for a vending machine. The parts illustra-ted do, however, constitute an operative testing device.

In the actual device the support I9 is returned to its operative position after each operation so that it will return any coins to the reject opening if inserted when the current is off. By constructing the stop 69 as shown in Figure 9, the stop I9 will be automatically returned to operative position by the action of the spring 54, and when so constructed the hinged armature 51 can be formed integral with the pole pieces 2| and 22.

One reason for inclining the upper or supporting edge of member i9 is to cause the coin toroll into the reject opening if the current is off at the time the coin is deposited, and another object is to effect a return to the reject opening of slugs that pass through the magnetic eld. Another important object is to allow certain adjustments to be made to compensate for variations in voltage.

It is evident that the alternating magnetic field cannot exceed that which will permit a silver coin After the silver coin has been deposited on the support, it must be prevented from rolling into the reject opening. Since the support is inclined, the effect of gravity will be resolved into two components, one of which is vertical and the other parallel with the inclined surface of the support. By means of a special tool, the inclination of the support can be adjusted to conform to the strength of the magnetic eld,

Although the operation has been explained in connection with a silver dollar, the apparatus will function equally well with a fifty cent piece and with a quarter.

Having described the claimed as new is:

1. An apparatus for separating round silver coins from coins of other metals, but of the same size, and shape, comprising an anvil of elastic metal, having an impact surface at its upper end, means for directing a coin edgewise onto the impact surface, along a path inclined thereto, whereby it will rebound along a path and at a velocity corresponding to its modulus of elasticity, a support spaced from the anvil in position to receive a silver coin after its rebound, the support being incilned towards the anvil there being an open space between the anvil and the support, forming a reject opening, means interposed between the anvil and the support for producing an alternating magnetic flux across the rebound path, the strength of the flux being adjusted to the maximum for the passage of silver coins therethrough, the degree of the inclination of the inclined support being so proportioned to the ux density that the silver coin will not roll into the reject opening, and means for removing the support after a predetermined time interval whereby a coin resting thereon will drop by the action of gravity.

2. An apparatus for separating round silver coins from coins of other metal of the same size, comprising, in combination, an anvil of elastic material having a horizontally inclined impact surface at its upper end, means for directing a freely falling coin edgewise onto the impact surface, whereby the coin will rebound along a path, and at a velocity corresponding to its modulus of elasticity, a stop forming the end of the rebound path, a movable support adjacent the stop, inclined towards the anvil, in position to receive and support the coin after its rebound, there being a reject opening between the anvil and the support, means for subjecting the rebound path, at a point between the anvil and the support, to an alternating magnetic flux of a density that will barely permit a silver coin to pass, the degree of inclination of the support being so proportioned to the flux density that the silver coin will not roll past the magnet and into the reject opening, and means for removing the support and directing the coin into a coin compartment.

3. An apparatus for separating round silver coins from coins of other metal of the same size and shape, comprising in combination, an anvil of elastic material having a horizontally inclined impact surface at its upper end, means comprising a guide member having an edge slightly inclined to the vertical for guiding a coin, means for holding a coin in contact with the guide edge while falling, means for directing a freely falling coin edgewise onto the impact surface of the anvil, whereby the coin will rebound along a path, and at a velocity corresponding to its modulus of elasticity, a stop forming the end of the rebound path, a movable support adjacent the stop, inclined towards the anvil, in position to receive and support the coin after its rebound, means for subjecting the rebound path, at a point between the anvil and the support, to an alternating magnetic flux of a density that will barely permit a silver coin to pass, there being a reject opening between the anvil and the support, and means for removing the support and directing the coin into a coin compartment.

4. An apparatus for separating round silver invention, what is antispamV coins from coins of other metal'of thesamesize and shape, comprising, in combination,` an anvil of elastic material having a horizontally inclined impact surface at its upper end,` meansfor directing a freely falling coin edgewise onto the impact surface, whereby the coin will rebound along a path, and at a velocity corresponding to its modulus of elasticity, a stop forming the end of the rebound path, a movable support adjacent the stop, inclined towards the anvil, in position to receive and support the coin after its rebound, means comprising an alternating current electromagnet, positioned between the anvil and the support, for subjecting the rebound path to `an alternating magnetic flux of such density that it will barely permit a silver coin to pass, there being a reject opening between the anvil and the support, means for removing the support after the coin has reached the same, and means for de-energizing the electromagnet as the support is being removed.

5. An apparatus for separating round silver coins from coins of other metal of the same size and shape, comprising in combination, an anvil of elastic material having a horizontally inclined impact surface at its upper end, means co-mprising a memberhaving an edge slightly inclined to the vertical for guiding a coin, means for holding a coin in contact with the guide edge while falling, said guide member and coin holding means serving also as means for directing a freely falling coin edgewise onto the impact surface of vthe anvil, whereby the coin will rebound along a path, and at a velocity corresponding to its modulus of elasticity, a stop forming the end of the rebound path, a movable support adjacent the stop, in position to receive and support the coin after its rebound, the upper surface of the support being downwardly inclined in the direction of the anvil, there being a reject opening between the support and the anvil, means for subjecting the rebound path, at a point between the anvil and the support, to an alternating magnetic flux of a density that will barely permit a i silver coin to pass, andmeans for removing the a path, and at a velocity corresponding to its modulus of elasticity, a stop forming the end of the rebound path, a movable support adjacent the stop, inclined towards the anvil, in position to receive and support the coin `after its rebound,

means for subjecting the rebound path, at a point between the anvil and the support, to an alternating magnetic ux of a density that will barely permit a silver coin to pass, there being a reject opening between the support and the anvil,

' means for removing the support and directing the coin into a coin compartment, means for latching the support in inoperative position, and means for unlatching the support and returning it tooperative position.

'7. An apparatus for separating round silver coins from coins of other metals, but of the same size, comprising an anvil of elastic metal, having an impact surface at its upper end, means for directing a coin edgewise onto the impact surface, along a path inclined thereto, whereby it will rebound along a path and at a velocity corresponding to its modulus ofelasticity, a stop forming the end of the rebound path, a movable support spaced from the anvil in position to receive asilvercoinafter its rebound, the upper surface of the support being downwardly inclined in the direction of the anvil to produce a tendency for the coin to roll towardsthe anvil, there being an` open space between the anvil and the support, forming a reject opening, means for moving the support Vto inoperative position to release the coin, and means interposed between the reject opening and the support for producing an `alternating magnetic flux across the rebound path, the strength of the flux being adjusted to the maximum for the passage of the rebounding `silver coins therethrough.

8. A coin selecting and testing device, having a base comprising a plate normally occupying a vertical position, an anvil secured to the plate and provided with-an impact surface at its top, the plate having a hole at some distance above the -anvil through which a coin can be inserted, means for directing the coin so that it will strike the impact surface with its edge, the surface at the point of impact being inclined with respect to the path of the coin, `whereby it will rebound along a path angularly related'to the incidence path, a stop at the end of the rebound path, a movable support located below the stop in position to receive the coin at the end of its travel, the upper surface of the support being inclined downwardly toward the anvil, there being a reject opening between the support and the anvil, means comprising an electromagnet located between the anvil and the stop for subjecting the rebound path to an alternating magnetic ux, whereby a force is produced tending to resist the movement of a coin of conductive material therethrough, the flux strength being adjusted to barely permit a rebounding silver coin to pass, means for removing the support to permit the coin to drop, and means for stopping the production of magnetic flux when the coin is released by the support.

9. A coin selecting and testing device, having a base comprising a plate normally occupying a verticalposition, an anvil securedto the plate and provided with an upper impact surface, the plate having a hole at some distance above the anvil through which a coin can be inserted, means for directing the coin in its passage to the anvil so that it will strike the impact surface with its edge, the surface at the point of impact being inclined with respect to the path of the coin, whereby it will rebound along a path angularly related to the incidence path, a stop at the end of the rebound path, a movable support located below the stop in position to receive the coin at the end of its travel, the upper surface of the support being inclined downwardly toward the anvil, there being a reject opening between the support and the anvil, means comprising an electromagnet energized from a source of alternating current, located between the anvil and the stop for subjecting the rebound path to an alternating magnet flux whose density is adjusted to barely permit a rebounding silver coin to pass, whereby a force is produced tending to resist the movement of a coin of conductive material in its rebound passage from the anvil towards the stop and for resisting movement of the coin from the support towards the reject opening, means for removing the support to permit the coin to drop,

and means for de-energizing the electromagnet when the coin is released.

l0. An apparatus for use in separating silver coins from coins of similar size and shape, but made from metals having physical properties different from silver, comprisng in combination, a base provided with a substantially vertical chute of a size that will permit the largest coins ernployed to fall freely, a guide located in the chute and provided with a guide wall, means for urging a falling coin towards the guide wall and for subjecting it to a retarding force, comprising a pendulum, pivoted near its top, the edge of the pendulum facing the guide wall being normally inclined towards the guide wall in a downward direction, the pendulum being counter-balanced to normally maintain this position, and an anvil located in the path of the falling coin and provided with an impact surface inclined with respect to the path of the coin whereby the coin, after impinging thereon, will rebound along an upwardly and outwardly inclined path.

1l. An apparatus for use in separating silver coins from coins of similar size and shape, but made from metals having physical properties different from silver, comprising in combination, a base provided with a substantially vertical chute of a size that will permit the largest coins employed to fall freely, a guide located in the chute and provided with a guide wall, means for urging the coin toward the guide wall, and for subjecting the coin to a retarding force, an anvil located in the path of the falling coin and provided with an impact surface inclined with respect to the path of the coin whereby the coin, after impinging thereon, will rebound along an upwardly and outwardly inclined path, means for subjecting the rebound path to an alternating magnetic fiux for producing a retarding influence on the coin, a stop at the end of the rebound path, a movable support located adjacent the stop to receive and support the coin, there being a reject opening between the support and the anvil, the upper surface of the support inclining downwardly towards the reject opening to provide a gravitational component tending to roll a circular coin towards the reject opening, the strength of the magnetic flux being so adjusted that it will barely permit a rebounding silver coin to pass and the degree of inclination of the supporting surface being so proportioned to the strength of the flux that the circular silver coin will be held from rolling towards the reject opening, and means for removing the support to permit the coin to drop.

12. An apparatus for use in separating silver coins from coins of similar size and shape, but made from metals having physical properties different from silver, comprising in combination, a base providedwith a substantially vertical chute of a size that will permit the largest coins employed to fall freely, a guide located in the chute and provided with a guide wall, means for urging the coin toward the guide wall, and for subjecting the coin to a retarding force, an anvil located in the path of the falling coin and provided with an impact surface inclined with respect to the path of the coin whereby the coin, after impinging thereon, will rebound along an upwardly and outwardly inclined path, means for subjecting the rebound path to an alternating magnetic flux of a density that will barely permit a silver coin to pass, for producing a retarding influence on the coin, a stop at the end of the rebound path, a movable support located adjacent the stop to receive and support the coin, the upper surface of the support being downwardly inclined in the direction of the anvil, there being a reject opening between the support and the anvil, means comprising a plunger for engaging the top of the coin and forcing it downwardly against the support, and means responsive to the pressure of the coin on the supporting surface for moving the support to inoperative position.

13. The method of separating metal coins of the same size and shape, having different physical properties, comprisng, dropping them edgewise onto an elastic surface inclined with respect to the path of the falling coins, whereby they will rebound along an upwardly inclined path, subjecting the rebound path to a fluctuating magnetic flux, for exerting a retarding action on the rebounding coins, supporting the coins that have passed through the magnetic flux within the infiuence of the magnetic field, subjecting the coins while thus supported to a component of the force of gravity tending to return it through the magnetic field to a reject opening, and then removing the support.

14. The method of separating silver coins from coins of other metals, of the same size and shape and having different moduli of elasticity which consists in dropping the coins separately from the same height and on edge onto an elastic metal surface, inclined with respect to the path of the coins, whereby they will rebound along an upwardly inclined path at velocities corresponding to their elasticities, subjecting the rebound path to a fluctuating magnetic flux of a density slightly below the maximum for passing silver coins, supporting the silver coins that pass the flux within the iniiuence of the magnetic ux, on a surface inclined toward the elastic surface whereby there will be a component of the force of gravity tending to return the coins through the magnetic field to a reject opening, and then removing the support and permitting the coin to drop.

15. In a coin testing device having an anvil for effecting a rebound resiliency test, means for directing coins of different sizes onto the anvil so that all will travel in parallel incidence paths regardless of size, said means comprising a guide plate having one edge downwardly ranging to form a guide, a pendulum mounted for free swinging movement about a pivot and having a downwardly extending arm having a guide edge that faces the guide edge of the guide plate, the two guide edges being inclined towards each other in a downward direction whereby a downwardly tapered passage is formed, the width of the passage at the level of the pivot being suicient to receivethe largest coin used and the normal width of the passage at its lower end being less than the diameter of the smallest coin used, the pendulum being swingable to permit the largest as well as the smallest coins to pass.

ERNEST O. EASON. 

